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| n | a(n) |
|---|---|
| 1 | -1 |
| 2 | 0 |
| 3 | -3 |
| 4 | -5 |
| 5 | -16 |
| 6 | -39 |
| 7 | -105 |
| 8 | -272 |
| 9 | -715 |
| 10 | -1869 |
| 11 | -4896 |
| 12 | -12815 |
| 13 | -33553 |
| 14 | -87840 |
| 15 | -229971 |
| 16 | -602069 |
| 17 | -1576240 |
| 18 | -4126647 |
| 19 | -10803705 |
| 20 | -28284464 |
| 21 | -74049691 |
| 22 | -193864605 |
| 23 | -507544128 |
| 24 | -1328767775 |
| 25 | -3478759201 |
| 26 | -9107509824 |
| 27 | -23843770275 |
| 28 | -62423800997 |
| 29 | -163427632720 |
[-1,0,-3,-5,-16,-39,-105,-272,-715,-1869,-4896, -12815,-33553,-87840,-229971,-602069,-1576240, -4126647,-10803705,-28284464,-74049691,-193864605, -507544128,-1328767775,-3478759201,-9107509824, -23843770275,-62423800997,-163427632720] |